1. Field of the Invention
The present invention relates to buoyant aircraft, and more particularly to buoyant aircraft having internal structural support components exhibiting a geodesic configuration.
2. Description of the Related Art
In recent years, air vehicles designed for transporting passenger and cargo have undergone many changes. Driven by rapidly developing new technologies and the influx of many new companies into global commerce, various body and engine designs and modifications have been developed resulting in aircraft capable of carrying greater passenger and cargo payloads for greater distances and for longer times. But many of these aircraft are expensive to develop and produce, and improvements including increases in engine efficiencies, wing aerodynamics and vehicle size have only provided limited gains.
The cost of airborne transport vehicles can be reduced significantly by designing for lower speed and altitude, and using buoyant lift to replace the aerodynamic lift produced by expensive-to-build and expensive-to-fly wings. The size of the vehicle and its associated payload capacity must be large enough, however, to compensate for the slower cruise speed.
Typically, airships of this type require landing gear that will adequately handle the weight associated with the large loads that such vehicles are capable of carrying.
U.S. Pat. No. 4,052,025 to Clark et al. discloses an airborne vehicle that uses buoyant cells pressurized to augment the craft's lift. The majority of the lift is produced by the wings and an aerodynamically shaped fuselage defining a lifting body that imparts considerable aerodynamic lift to the aircraft when in flight in an airstream with a minimum of aerodynamic drag. The body of the aircraft is a rigid exoskeleton consisting of a web of tension members helically wrapped around the fuselage. Propulsion is provided by a combination of jet engines and turboprop engines. Other aircraft that are known to use buoyant cells to augment lift produced predominantly by wings include those shown in U.S. Pat. No. 5,425,515 to Hirose, U.S. Pat. No. 3,907,218 to Miller, U.S. Pat. No. 3,913,871 to Miller, U.S. Pat. No. 4,889,297 to Ikeda, U.S. Pat. No. 3,032,298 to Callahan, and U.S. Pat. No. 3,856,238 to Malvestuto, Jr.
Typical landing gear arrangements that are used on aircraft have some width relative to the height of the center of gravity that allows a wide enough stance that the aircraft is stable in roll during ground operation. Large commercial aircraft may have a gear stance of 50 feet to achieve stable operation with their relatively low center of gravity and this is narrow enough to operate on typical Class VI 200 feet wide runways. As vehicle size increases, gear width increases to an unacceptable width that precludes operation on even the largest commercial runways. The wide stance provides plenty of stability for good vehicle performance, but for a transportation system that has to operate within existing airport infrastructure, this width is unacceptable.
Against this background of known technology, the applicants have developed a new landing gear arrangement for a buoyant air vehicle, which provides substantial stability for the air vehicle, while reacting turning and braking loads.